A political theory of social organization advocating limits on the private ownership of industry. The word first appeared in France and Britain in the early 19th century. It covers a wide range of positions from communism at one extreme to social democracy at the other. Most socialists believe that the community as a whole should own and control the means of production, distribution, and exchange to ensure a more equitable division of a nation’s wealth, either in the form of state ownership of industry, or in the form of ownership by the workers themselves. They have also often advocated replacing the market economy by some kind of planned economy. The aim of these measures is to make industry socially responsible, and to bring about a much greater degree of equality in living standards. In addition, socialists have argued for provision for those in need, as in the welfare state. Socialism as a political ideal was revolutionized by Karl Marx in the mid-19th century, who tried to demonstrate how capitalist profit was derived from the exploitation of the worker, and argued that a socialist society could be achieved only by a mass movement of the workers themselves. Both the methods by which this transformation was to be achieved and the manner in which the new society was to be run remained the subject of considerable disagreement and produced a wide variety of socialist parties.

These debates have been somewhat overshadowed in recent years by the question of whether socialism is viable at all as an alternative to capitalism. Most Western socialists now opt for social democracy, others for market socialism. It is only in certain developing countries that traditional socialist aims still attract support.